Analytical assays have become an increasingly important aspect of medical diagnosis and treatment. Periodic assays allow physicians to monitor trends in physiological concentration of a biologic within an individual. Unfortunately, the costs, inconvenience and discomfort associated with collecting and handling blood samples precludes more extensive testing. Thus, there exists a need for a method utilizing biological fluids for biochemical assays which are noninvasively obtainable yet correlate with blood plasma concentrations of a biologic.
Further, drug and alcohol abuse are common problems in today's society, destroying the afflicted individuals and adversely effecting those close to them. While drug and alcohol abuse are problems for society as a whole, employers are particularly susceptible to its deleterious effects. In the modern work place, focused and efficient employees are essential for employers who wish to maintain high quality and productivity while minimizing costs and absenteeism. In order for employees to attain and sustain high productivity, it is crucial that each employee be both healthy and alert. An employee who is in poor health or who is inattentive reduces efficiency and may increase the risk of injury to themselves and other employees. Reduced productivity and quality, increased health care costs and the potential for long term abuse are only three problems an employer may encounter when an employee abuses drugs or alcohol.
In an effort to combat drug and alcohol abuse in the work place, many employers require employees to undergo mandatory drug testing. These tests, which are usually spontaneously ordered, generally require the employee to leave his place of business and travel to a nearby test facility. Alternatively, the testing could take place at the work site but many of these tests require a urine sample that naturally involves providing the employee with at least a minimum of privacy. The present manner of testing therefore results in at least two problems: 1) the employee is required to leave their job to undergo testing when they could otherwise be working; and 2) the privacy required by urine tests affords the employee the opportunity to submit a fraudulent sample (e.g., the employee could obtain a sample from another person and submit that drug free sample for testing). Thus, it would be desirable for an employer to have a method of testing an employee at their place of business, with only a minimum level of personal inconvenience to the employee. Alternatively, a similar method is useful in assisting a law enforcement officer preserve a suspect saliva sample for later forensic testing, e.g., to determine an individual's blood alcohol or other drug level. As a method of sparing the inconvenience and expense associated with laboratory drug testing, it would also be desirable if a qualitative test could be performed at the time of saliva collection to determine if quantitative testing is justified.
The present invention to provides a method of preserving saliva in a liquid solution for subsequent chemical assays. This method allows the employee to remain at his or her place of business, require only a minor inconvenience during testing and provide the necessary safeguards against submission of fraudulent tests while insuring that an accurate and precise drug test can be taken at a later time.
The present invention is also useful in providing a qualitative, instantaneous test for a drug after the saliva sample has been tamper-proof sealed.